1. Filed of the Invention
The present invention relates to a card connector, and more particularly to a card connector capable of reliably holding an inserted card.
2. Description of the Prior Art
Known IC cards have memory and/or an IC for serving as a control circuit. By loading such an IC card into electronic apparatuses such as cellular phones, telephones, PDAs, cameras and the like, functions of these electronic apparatuses can be enhanced. Examples of such IC cards include memory cards such as Subscriber Identity Module Card (SIM card), Multi Media Card (MMC), Smart Media, Secure Digital Card (SD card), Memory Stick, and Compact Flash Card.
Card connectors are provided for connecting such cards to circuit boards of the electronic devices. Switches have been designed into such conventional card connectors for the purpose of detecting the presence of inserted cards. See, for example, U.S. Pat. No. 5,511,986. Generally a switch includes an unmovable contact and a movable contact. The unmovable contact and the movable contact are normally spaced-apart. When the card is inserted into the card connector, the movable contact is deflected to contact with the unmovable contact by the inserted card. Therefore, the switch is actuated by the presence of the inserted card.
Another design for detecting the insertion and/or extraction of an card is disclosed in U.S. Pat. No. 6,547,601 B2, issued to Oguchi. The Oguchi card connector includes a movable contact located on one side of a frame, and a metallic shell having a side plate positioned at side edges of the frame to serve as an unmovable contact of a switch.
However, in the above structure of the detector switch used in the conventional card connector, the movable switch terminal is easily to be intolerant and out of condition after being repeated deflected by the inserted card. Moreover, the card itself is of dimension tolerance. When the card is of negative dimension tolerance, the movable contact of the switch may not get sufficient pressing force from the inserted card, resulting in an unreliable connection between the movable contact and the unmovable contact and rendering the switch inoperative. When the card is of positive dimension tolerance, the movable contact of the switch may accept excessive pressing force from the inserted card and easily to be damaged, resulting in a short life-span thereof. As the size of connectors decreases, it has become extremely desirable for connectors to have improved switch contacts to solve the above-mentioned shortcomings.
Subsequent efforts to provide a card connector structure characterized by modifying the unmovable contact is disclosed in U.S. Pat. No. 6,692,277 B2 and assigned to the same assignee of this invention. A switch in this patent includes a pair of spring switch contacts. Although this design is used in many applications, there is broadly space for improving.
Therefore, The present invention is directed to further improvements in switch contacts structures to solve one or more of the above myriad of interrelated problems presently occurring in card connectors.